This competitive renewal application for continued support of the Undergraduate Minority Summer Internship Program affiliated with the graduate Training Program in Environmental Health Sciences (T32- ES07155) represents the continuation of an extremely successful program targeting undergraduate students for exposure to environmental health sciences. The short term goal of our summer internship program is to support research training in a number of diverse areas relevant to environmental health intended for undergraduate minority students. We have, as our long-term goal, the attraction of minority scientists into graduate programs and careers in the environmental health sciences. Our proposal is to support minority students in our summer long laboratory based program. Since our last competing renewal we have enlarged the program to include 16 applicants per year who complete a 10 - week summer research internship under the supervision of faculty members who are also members of the Biological Science in Public Health (BPH) program at the Harvard School of Public Health. The BPH program has co-sponsored this highly successful internship since 1989 with an exclusive targeting of minority students since 1993. Faculty who are preceptors on the graduate level Training Program in Environmental Health Sciences join the larger group of preceptors within the BPH program to act as preceptors for summer interns. Up to 269 applicants for the 16 positions are rigorously screened and the admitted students select their areas of research from material provided before arrival and after two days of oral presentation on potential research opportunities. Research areas include environmental toxicology; mutagenesis; DMA damage and repair; cell cycle progression; signal transduction; gene regulation; molecular epidemiology; environmental assessment. The environment is one that is extremely rich and during the 10 - week internship the summer minority interns are specifically targeted for inclusion in a number of intern program related events that are rich in their scientific content.